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The extractive separation of tellurium (IV) from hydrochloric acid media with tri-n-butyl phosphate (TBP) in kerosene was investigated. The dependence on the extraction of tellurium species, concentrations of tellurium and TBP, extraction time and stage, organic/aqueous ratio, and interferences from coexist metallic ions were examined and are discussed. Besides, the stripping agent and stripping time were also studied. It was found that the extraction reaction corresponds to the neutral complex formation mechanism and the extracted species is TeCl4 · 3TBP and that the extraction process is exothermic. The thermodynamic parameters of enthalpy (ΔH), entropy (ΔS), and free energy (ΔG) of the extraction process were evaluated at -26.2 kJ · mol(-1), -65.6 J · mol(-1) · K(-1), and -7.0 kJ · mol(-1), respectively at 293 K.

The relative performance figure of merits was investigated for the two most common analytical methods employed for carbonyl compounds (CC), for example, between high performance liquid chromatography (HPLC)-UV detector (with 2,4-dinitrophenylhydrazine (DNPH) derivatization) and thermal desorption (TD)-gas chromatography (GC)-mass spectrometry (MS) (without derivatization). To this end, the suitability of each method is assessed by computing the relative recovery (RR) between the gas- and liquid-phase standards containing a suite of CC such as formaldehyde (FA), acetaldehyde (AA), propionaldehyde (PA), butyraldehyde (BA), isovaleraldehyde (IA), and valeraldehyde (VA) along with benzene (B) as a recovery reference for the GC method. The results confirm that a TD-GC-MS is advantageous to attain the maximum recovery for the heavier CCs (i.e., with molecular weights (MW) above BA-MW ≥ 74). On the other hand, the HPLC-UV is favorable for the lighter CCs (like FA and AA) with the least bias. Such compound-specific responses for each platform are validated by relative ordering of CCs as a function of response factor (RF), method detection limit (MDL), and recovery pattern. It is thus desirable to understand the advantages and limitations of each method to attain the CC data with the least experimental bias.

The present study describes the conductometric and spectroscopic study of the interaction of reactive anionic dyes, namely, reactive red 223 and reactive orange 122 with the cationic surfactant cetyltrimethyl ammonium bromide (CTAB). In a systematic investigation, the electrical conductivity data was used to calculate various thermodynamic parameters such as free energy (ΔG), enthalpy (ΔH), and the entropy (ΔS) of solubilization. The trend of change in these thermodynamic quantities indicates toward the entropy driven solubilization process. Moreover, the results from spectroscopic data reveal high degree of solubilization, with strong interactions observed in the cases of both dyes and the CTAB. The spontaneous nature of solubilization and binding was evident from the observed negative values of free energies (ΔG p and ΔG b).

Introduction: Artemisia annua is a rich source of biologically active substances such as terpenoids, coumarins and polyacetylenes. These chemicals have been reported to show beneficial pharmacological properties such as antitumor and antibacterial activities. In genetically transformed root cultures of A. annua, three bioactive metabolites, namely, ponticaepoxide (an insecticidal polyacetylene, 1), drimartol A (an anticancer sesquiterpene coumarin, 2) and (Z)-7-acetoxy-methyl-11-methyl-3-methylene-dodeca-1,6,10-triene (a new anticancer sesquiterpene, 3) were isolated and identified in our recent work. However, no quantitative analysis methods for any of them are yet available, nor for their simultaneous analysis., Objective: To develop an HPLC-PAD method for simultaneous determination of 1, 2 and 3 in hairy root cultures of A. annua., Methodology: HPLC operating conditions were optimised and the chromatographic separation was performed on a C(18) column with a gradient acetonitrile : water as mobile phase., Results: Linear relationships within the range of investigated concentrations were observed for the three metabolites with their correlation coefficients greater than 0.997. The method was validated for repeatability (RSD <3.59%) and intra- and inter-day precision (RSD <3.1%) with recovery between 94.8 and 107.6% and the RSD less than 3.40%. The method was successfully applied to the time-course of accumulation of the bioactive compounds in genetically transformed root cultures of A. annua., Conclusion: The HPLC-PAD method developed for the simultaneous determination of three bioactive metabolites 1, 2 and 3 was simple, reproducible and sensitive., (Copyright © 2010 John Wiley & Sons, Ltd.)

Background: Children who are receiving parenteral nutrition are at risk of aluminum overload, which may contribute to such side effects as osteopenic bone disease. The aim of the present study is to determine the aluminum contamination of parenteral nutrition solutions and their components, and to assess the aluminum status of children on long-term parenteral nutrition., Methods: Aluminum concentrations were determined by graphite furnace absorption spectroscopy in components and in final parenteral nutrition solutions. The urinary aluminum excretion and plasma aluminum concentration were determined in 10 children on long-term parenteral nutrition., Results: The mean aluminum concentration in the administered parenteral nutrition solutions was 1.6 +/- 0.9 micromol x l(-1)(mean +/- standard deviation (SD)). The resulting mean aluminum daily intake of the 10 patients was 0.08 +/- 0.03 micromol x kg(-1) x day(-1)., Conclusions: Compared to two previous studies performed in 1990 and in 1995 in our hospital, the aluminum contamination of parenteral nutrition solutions and the daily aluminum intake of the children seemed to decrease. However, the plasma aluminum concentration and daily urinary aluminum excretion of the children still remain above normal standards. The children had no clinical symptoms of bone disease but aluminum accumulation in tissue can not be excluded. To prevent this iatrogenic toxicity, the aluminum contamination of parenteral nutrition should be assessed regularly.

Background: The extent of aluminum contamination in parenteral nutrition solutions was measured in 35 different commercial products, including amino acids, electrolytes, glucose, lipids, vitamins trace elements, and albumin. The extent of aluminum contamination in substances used as raw material for preparation of parenterals was also measured. Chemicals from different manufacturers and of different quality grades were analyzed individually., Methods: The measurements were done by atomic absorption spectrometry., Results: The results showed that the same product might have different aluminum content depending on the manufacturer, either for commercial formulations or substances. The highest contaminated chemicals included cystine, NaOH, vitamin C, biotin, gluconate, and Fe and Cr salts. The lowest contaminated chemicals included lipids, apolar amino acids, glucose, HCI, acetic acid, KCl, NaCl, and heparin. Among commercial products, the major contamination rates appeared in calcium gluconate, followed by trace elements, some vitamins, bicarbonate, phosphates salts, and heparin., Conclusions: Comparing the aluminum in commercial products and substances, it can be concluded that the contamination may occur in parenterals because aluminum is present naturally in the chemicals. However, when the composition and concentration of the parenteral solution are considered, the contamination of calcium gluconate, trace elements, some vitamins, phosphates, bicarbonate, and heparin cannot be related only to the raw substances. The aluminum level present in these commercial formulations is too high to come only from the substances; therefore, it is possible that one of the steps of the manufacturing procedure is responsible for elevating the contamination of these products.

Background: Trace elements have been shown to contaminate total parenteral nutrition (TPN) solutions., Methods: This study used the multi-elemental technology of inductively coupled plasma-mass spectrometry to demonstrate the extent to which trace elements were present in amounts above (ie, as contaminants) or below expected levels in eight TPN component solutions., Results: Of the 66 trace elements scanned, there were 12 trace element contaminants in amounts >1 microg/L (zinc, copper, manganese, chromium, selenium, boron, aluminum, titanium, barium, vanadium, arsenic, and strontium) in the eight component solutions studied. Trace element contaminants were present in all solutions, and different trace elements contaminated the solutions at various concentrations. Component solutions of amino acid, potassium chloride, calcium gluconate, and sodium chloride contained the greatest numbers of trace element contaminants, whereas the lowest numbers were present in sterile water and magnesium sulfate. Interlot and intermanufacturer variations were apparent. Measured concentrations of trace elements in the multi-trace element additive solution also were higher than the labeled values. A comparison of the amounts of contaminated trace elements delivered by a typical TPN mixture relative to the amounts typically absorbed by the gastrointestinal tract indicates that the inadvertent delivery of trace elements from contaminated TPN solutions may be substantial., Conclusions: All eight components tested were contaminated with trace elements not intended to be present in the product, and similarly, the multi-trace element component contained trace elements either above or below that which the label claimed.

Background: Patients who receive home total parenteral nutrition (TPN) frequently are supplied with solutions up to 30 days in advance of anticipated use. The purpose of this study was to determine the stability of trace elements relative to time and temperature conditions, in a typical adult TPN solution stored in a usual home environment by examining variations in delivery of intended trace elements and inadvertent trace element contamination., Methods: Trace element concentrations were determined using inductively coupled plasma-mass spectrometry technology. The effect of the delivery apparatus, storage duration (36 hours or 30 days) after compounding, and storage temperature (4 degrees C or 20 degrees C) were examined., Results: The delivery apparatus contaminated the delivered TPN solution with cobalt but did not alter trace elements formulated into the TPN solution. Storage duration and temperature significantly decreased three (Zn, Cu, and Mn) of the six trace elements formulated into the TPN solution. Higher temperatures and longer duration of storage accelerated this decrease. Boron, Al, V, Ti, Ba, Sr, and CO were the trace elements that appeared as contaminants during storage. Boron, Al, V, and Ti contamination decreased with higher temperatures and longer duration of storage., Conclusions: Longer storage duration and higher storage temperature progressively reduced the deliverable concentrations of trace elements specifically formulated into the TPN solution and also of those trace elements that were not formulated into the TPN solution but that appeared as contaminants.

Reliable and uncomplicated methods for detection of free formaldehyde in products preserved with formaldehyde donors are desirable to decrease the risk of allergic contact dermatitis. The aim of this study was to develop a method that could be used in clinics and workplaces for quantification of free formaldehyde in products preserved with formaldehyde donors. The method developed is named the closed container diffusion (CCD) method. Formaldehyde in a sample is allowed to evaporate in a closed container and react with 2,4-dinitrophenylhydrazine coated on a glass fibre filter. The hydrazone formed is analyzed with HPLC. The method was tested on 3 different formaldehyde donors, imidazolidinyl urea, diazolidinyl urea and 2-bromo-2-nitropropane-1,3-diol, using 4 different cream bases. The results obtained with this method accord, with those obtained with the official method within the European Union (EU). The method is sensitive enough for analysis of patients' products and for control of labelled amounts of formaldehyde in technical products without solvent extraction. As a result of our studies, we observed a risk of exceeding the labelling limit for free formaldehyde in cosmetic products when using the highest amount of diazolidinyl urea allowed within the EU.

We compared the abilities of three solutions (bicarbonate-free glucose-phosphate Ringer's solution (EP II), lactated Ringer's solution and physiologic saline solution) to preserve pig cornea by measuring phosphate metabolites with 31P NMR spectroscopy. EP II preserves corneal viability better than others, and preserving extracted cornea also is better than preserving the whole eye.

We hypothesized that retention of parenterally delivered calcium (Ca) and phosphorus (P) is affected by the ratio of the delivered minerals and that a 1.7:1 ratio would be optimal since this is the ratio of retention of these minerals by the fetus. Forty-one very low birth weight (VLBW) infants were randomly assigned to one of three total parenteral nutrition (TPN) solutions that were different only in their Ca:P ratios: 2:1 (76 mg/kg/day Ca and 38 mg/kg/day of P), and 1.3:1 (58 mg/kg/day Ca and 45 mg/kg/day P), and 1.3:1 (58 mg/kg/day of Ca and 45 mg/kg/day of P). Serum levels of calcium, phosphorus, and alkaline phosphatase, retentions of calcium and phosphorus and urinary cyclic AMP levels were measured after 48 h on the assigned Ca to P ratio. Calcium retentions were higher with the 2:1 and 1.7:1 ratios and phosphorus retentions were higher with the 1.3:1 and 1.7:1 ratios. The 1.7:1 ratio allowed for the highest absolute retention of both minerals and was the closest to published in utero accretion of calcium and phosphorus. The serum and urine studies demonstrated no abnormalities on any of the three ratios. Cyclic AMPs were not different among groups and were not elevated compared to previous reports suggesting that none resulted in parathyroid hormone (PTH) stimulation. We conclude that the 1.7:1 ratio is better than higher or lower ratios for delivery of calcium and phosphorus in TPN solutions at the quantities studied.

The extent of aluminum (Al) contamination in parenteral nutrition (PN) solutions for infants is not known. Aluminum was measured in 136 samples from various commercially available components that are used with PN. Results showed Al content varied widely among different components. The same chemical may have a different Al content depending on the manufacturer. However, Al contents were similar among lots from the same manufacturer for the same chemical. Aluminum contamination was arbitrarily classified as high (greater than 500 micrograms Al/liter), intermediate (51-500 micrograms Al/liter) or low (less than or equal to 50 micrograms Al/liter). The high group included most calcium and phosphorus containing salts, 1 multivitamin preparation, folic acid, ascorbic acid and concentrated (25%) albumin. The intermediate group included sodium lactate, potassium phosphates, zinc and chromium chloride, multitrace metal preparation, and 5% plasma protein. The low group included amino acids, sterile water and dextrose water, chloride salts of sodium, potassium, calcium, copper and chromium, sodium phosphates, magnesium sulphate, zinc sulphate, vitamin B12, vitamin K1, 1 multivitamin preparation, soybean oil emulsion and heparinized (2 U/ml) saline. PN solutions made from high Al components may contain up to 300 micrograms Al/liter. Calcium gluconate contributed greater than 80% of the total Al load from PN. Lowering of Al content in calcium gluconate in addition to use of specific low Al components offers the opportunity to significantly lower the Al concentration of the final PN solution and theoretically may achieve an Al content as low as 12 micrograms/l.(ABSTRACT TRUNCATED AT 250 WORDS)

Fat emulsions are increasingly utilized as intravenous calorie sources in patients requiring total parenteral nutrition. In the United States, they are traditionally administered separate from the dextrose/amino acid solution because of concern regarding physical stability and clinical safety when fat emulsions are administered, having been mixed with the dextrose solution. The separate infusion entails multiple manipulations of the infusion system with increased risk of contamination and sepsis and increased cost in maintaining two infusion lines. This prospective sequential two-phase clinical study evaluated solution compatibility and clinical safety of an admixture of fat emulsion (Intralipid 20%), dextrose, amino acids (Veinamine 8%), electrolytes, vitamins, and trace minerals. Continuous infusion of this solution in 25 adult patients from 2 to 35 days did not result in any adverse clinical reactions or abnormal laboratory parameters. Gross, visual examination and in vitro analysis of the admixture solutions revealed no physical instability or changes in fatty acid composition in admixture solutions stored at 4 degrees C for up to 6 weeks.

On grinding hard metal alloys containing cobalt, the dissolution of cobalt during 5 days was studied for nine commercial cutting fluids. After 1 day, a major part of the cobalt liberated from the material ground is found in solution. This percentage decreases when grinding is continued using the same coolant fluid. Only a small fraction of the cobalt is found in particles in the circulating fluid. The bulk must be in the sediment in the storage tank, where it does no harm to the workers' skin. The final concentration of cobalt found in some fluids may be hazardous.

Ultrasonic and nuclear magnetic resonance properties of media rich in water are investigated. The chemical shift of the water proton in pure water, aqueous solutions of tertiary butanol, and sodium chloride is shown to be linearly correlated to the reciprocal of sound speed in these media. A new method of determining the self-diffusion coefficient of water by using acoustic nonlinearity and sound speed is proposed. The method is tested on a variety of media that include pure water, aqueous solutions of glycerol, serum albumin, egg constituents, plant tissues, frog muscle and liver, and excised human tissues. In all the cases the results are found to compare closely to diffusion coefficients measured by magnetic resonance. The results presented here indicate that the acoustic and magnetic resonance modalities, though inherently different in their origin, can provide closely related information on the properties of water.

More attention is being given to the essential trace elements in human nutrition, although there is much to be learned concerning requirements, function, and interactions. The extensive use of total parenteral nutrition (TPN) provides an opportunity for further study. To date, little attention has been paid to selenium (Se), an element for which both a deficiency and toxic state can exist. In a program to evaluate the effects of long-term TPN on Se nutriture, a avriety of solutions used in TPN have been analyzed. Se was not present in detectable levels in the following solutions: sodium acetate, Freamine II, NaCl, potassium phosphate, KCl, Folvite, Liquaemin Na, CaCl2, MgSO4, and NaHCO3. The solutions containing significant amounts of Se were: 50% dextrose 0.27 +/- 0.04 microgram/ml and 20% dextrose 0.27 +/- 0.08 microgram/ml (Travenol Laboratories); 50% dextrose 0.47 +/- 0.10 microgram/ml and 20% dextrose 0.35 +/- 0.07 microgram/ml (Abbott Laboratories); and 70% dextrose 0.33 +/- 0.08 microgram/ml (McGaw Laboratories). These data suggest that 200 to 400 microgram Se would be provided in the usual amounts of solution administered to an adult patient.